The deal is the largest Indian takeover of a foreign company, and creates the world's fifth-biggest steel company.

Why did Tata want Corus?

There is a recognition that for the Indian economy to continue its growth, its companies must look to compete on a global scale.

Tata is currently just the 56th biggest steel producer globally.

Buying Corus leapfrogs it to fifth place in the world steel-making rankings.

The takeover also gives it access to Corus technology as well as its production sites.

The Indian firm says it will be able to make savings on costs, from marketing to buying materials.

Why was Corus keen to be taken over?

In order to survive, Corus needs to extend its global reach just as much as Tata does.

A tie-up with Tata gives it, among other things, access to markets in India - one of the fastest-growing economies in the world - as well as access to low-cost materials.

If Corus had been bought by CSN, the same would have applied regarding Brazil.

What impact will this deal have on UK jobs?

Unions have expressed concern over potential job cuts at Corus. Of its 47,300 employees worldwide, 24,000 people work in the UK at sites including Port Talbot, Scunthorpe and Rotherham.

Tata has said there will be no job cuts in the early stages.

What about pensions?

The Corus pension fund has 166,000 members in the UK - including former British Steel workers. It is not badly off at present - with one union official describing it as in surplus and in a "robust" position.

Tata has pledged to increase contributions to the British Steel fund from 10% to 12% by 2009.

It will also be making a one-off payment of £126m to the Corus Engineering Steels Pension Scheme.

Is the purchase of a company from a developing nation a sign of the future?

There has been growing evidence of a shift in global business power, with foreign investment from developing countries now a major factor in the world economy.

The United Nations Conference on Trade and Development (Unctad) has confirmed the trend - with foreign direct investment from developing countries and transition economies, such as Russia and the former Soviet Union, rising 5% to $133bn (£70bn) in 2005.

The Tata deal is a further sign that India's economy is a force to reckoned with. Analysts expect a wave of takeovers by Indian firms to ensue around the world.

Previous Indian deals in Europe include the takeover of German group Betapharm by pharmaceutical firm Dr Reddy for $570m, as well as energy company Sulzon's acquisition of Belgian firm Eve Holding for $526m.

What does the purchase of a big European firm by a small Indian steel firm say about UK manufacturing?

Corus chief executive Jim Leng said that just as British Steel and Dutch group Hoogovens merged in 1999 because they felt they could not simply be national companies, Corus now felt it was "no longer sufficient to be European".

"This is a global industry," he said. "We have got to respond with passion, but with commercial passion.

"It's not about big companies and small companies, it's a matter of being globally commercial."